| Message ID | 1394945457-16212-1-git-send-email-lucien.xin@gmail.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
Hi! On Sun, Mar 16, 2014 at 12:50:57PM +0800, Xin Long wrote: > In ip6_append_data_mtu(), when the xfrm mode is not tunnel(such as > transport),the ipsec header need to be added in the first fragment, so the mtu > will decrease to reserve space for it, then the second fragment come, the mtu > should be turn back, as the commit 0c1833797a5a6ec23ea9261d979aa18078720b74 > said. however, in the commit a493e60ac4bbe2e977e7129d6d8cbb0dd236be, it use > *mtu = min(*mtu, ...) to change the mtu, which lead to the new mtu is alway > equal with the first fragment's. and cannot turn back. > > when I test through ping6 -c1 -s5000 $ip (mtu=1280): > ...frag (0|1232) ESP(spi=0x00002000,seq=0xb), length 1232 > ...frag (1232|1216) > ...frag (2448|1216) > ...frag (3664|1216) > ...frag (4880|164) > > which should be: > ...frag (0|1232) ESP(spi=0x00001000,seq=0x1), length 1232 > ...frag (1232|1232) > ...frag (2464|1232) > ...frag (3696|1232) > ...frag (4928|116) > > so delete the min() when change back the mtu. While the patch looks good it does not seem to apply cleanly on net. Maybe you could have a look? Thanks, Hannes -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Mar 17, 2014 at 7:20 AM, Hannes Frederic Sowa <hannes@stressinduktion.org> wrote: > Hi! > > > While the patch looks good it does not seem to apply cleanly on net. Maybe you > could have a look? > so sorry, a little mistake, post again. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 117c093..6184dfa 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1101,20 +1101,19 @@ static void ip6_append_data_mtu(unsigned int *mtu, unsigned int fragheaderlen, struct sk_buff *skb, struct rt6_info *rt, - bool pmtuprobe) + unsigned int orig_mtu) { if (!(rt->dst.flags & DST_XFRM_TUNNEL)) { if (skb == NULL) { /* first fragment, reserve header_len */ - *mtu = *mtu - rt->dst.header_len; + *mtu = orig_mtu - rt->dst.header_len; } else { /* * this fragment is not first, the headers * space is regarded as data space. */ - *mtu = pmtuprobe ? rt->dst.dev->mtu : - dst_mtu(rt->dst.path); + *mtu = orig_mtu; } *maxfraglen = ((*mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); @@ -1131,7 +1130,7 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, struct ipv6_pinfo *np = inet6_sk(sk); struct inet_cork *cork; struct sk_buff *skb, *skb_prev = NULL; - unsigned int maxfraglen, fragheaderlen, mtu; + unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu; int exthdrlen; int dst_exthdrlen; int hh_len; @@ -1213,6 +1212,7 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, dst_exthdrlen = 0; mtu = cork->fragsize; } + orig_mtu = mtu; hh_len = LL_RESERVED_SPACE(rt->dst.dev); @@ -1312,8 +1312,7 @@ alloc_new_skb: if (skb == NULL || skb_prev == NULL) ip6_append_data_mtu(&mtu, &maxfraglen, fragheaderlen, skb, rt, - np->pmtudisc >= - IPV6_PMTUDISC_PROBE); + orig_mtu); skb_prev = skb;
In ip6_append_data_mtu(), when the xfrm mode is not tunnel(such as transport),the ipsec header need to be added in the first fragment, so the mtu will decrease to reserve space for it, then the second fragment come, the mtu should be turn back, as the commit 0c1833797a5a6ec23ea9261d979aa18078720b74 said. however, in the commit a493e60ac4bbe2e977e7129d6d8cbb0dd236be, it use *mtu = min(*mtu, ...) to change the mtu, which lead to the new mtu is alway equal with the first fragment's. and cannot turn back. when I test through ping6 -c1 -s5000 $ip (mtu=1280): ...frag (0|1232) ESP(spi=0x00002000,seq=0xb), length 1232 ...frag (1232|1216) ...frag (2448|1216) ...frag (3664|1216) ...frag (4880|164) which should be: ...frag (0|1232) ESP(spi=0x00001000,seq=0x1), length 1232 ...frag (1232|1232) ...frag (2464|1232) ...frag (3696|1232) ...frag (4928|116) so delete the min() when change back the mtu. Signed-off-by: Xin Long <lucien.xin@gmail.com> --- net/ipv6/ip6_output.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-)